Andrew's 91GT Engine Thread
#136
Andrew, don't listen to those other guys, here's the best advice by far:
STOOPID!
...Note to self: if I'd just listen to my own advice, I'd be a LOT better off!
You're not running major-boost, so you should be fine as-is, ...ya twin-screw ****!
STOOPID!
...Note to self: if I'd just listen to my own advice, I'd be a LOT better off!
Take the head some where to be evaluted...and go from there.
Cars out there are running fine on stock pistons..rings...gasket..etc etc. (knock on wood) Just as yours was.
Cars out there are running fine on stock pistons..rings...gasket..etc etc. (knock on wood) Just as yours was.
#137
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Supercharged
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K.I.S.S. => Keep it simple STOOOPID!
That's what I want to do. I think at this point I probably should take a look at the rings and crank bearings. The car does have 136k miles, so there's got to be some wear, best to find out now rather than in 18 months and do it all again.
As for dishing the pistons... we'll see what the mad scientist says, but assuming we just use the thicker HG to make up for loss from decking - that's probably how I'll approach it. Stroker crank... no!
As for methanol injection, not really interested. As long as my compression doesn't go too high, I should be able to run my 8.Xpsi safely.
And BTW, I only had leakage into one cylinder. See post #2 where I'm holding the passenger head. You can see Cyl #7 has brown exhaust valves. All the others are grey. My AFR has always been pretty good, but if this is an indication of some other issue, I'm all ears.
That's what I want to do. I think at this point I probably should take a look at the rings and crank bearings. The car does have 136k miles, so there's got to be some wear, best to find out now rather than in 18 months and do it all again.
As for dishing the pistons... we'll see what the mad scientist says, but assuming we just use the thicker HG to make up for loss from decking - that's probably how I'll approach it. Stroker crank... no!
As for methanol injection, not really interested. As long as my compression doesn't go too high, I should be able to run my 8.Xpsi safely.
And BTW, I only had leakage into one cylinder. See post #2 where I'm holding the passenger head. You can see Cyl #7 has brown exhaust valves. All the others are grey. My AFR has always been pretty good, but if this is an indication of some other issue, I'm all ears.
#138
Ok... so lets say that the mad scientist looks at my heads and gives me a thumb up on getting it filled and resurfaced. If I want to get the block decked, this is going to raise my CR quite a bit potentially, right?
At that point, maybe I should look into dishing the pistons slightly to lower CR into a slightly safer range... Double black diamond... here I come!
At that point, maybe I should look into dishing the pistons slightly to lower CR into a slightly safer range... Double black diamond... here I come!
As far as dishing pistons go, anything is possible with $$$$... I debated for better part of a year if I should change things on my engine, but finally decided to just keep it simple and make it work like it was designed to. IMHO, your motor ran fine before, keep it like that. Just reassemble everything as close to factory tolerances as you can, you'll be fine.
#139
IMHO just keep it very simple. Only surface the block if it needs it.
Then find yourself another engine to 'play' with. Take that one to town, then when #1 goes you will have some empirical data to see how long it will really lasts and also have a long weekend to do the replacement.
my 2.2cents (Canadian)
Then find yourself another engine to 'play' with. Take that one to town, then when #1 goes you will have some empirical data to see how long it will really lasts and also have a long weekend to do the replacement.
my 2.2cents (Canadian)
#140
Its been a while and i honselty cant recall the price but it was actaully pretty cheap. I may have posted the price in a thread somewhere? Cool thing is...those dimensions are stored on a disc. Zero out the lathe and push a button and it replicated.....16 times. The tops have since been ceramic coated.
#141
Its been a while and i honselty cant recall the price but it was actaully pretty cheap. I may have posted the price in a thread somewhere? Cool thing is...those dimensions are stored on a disc. Zero out the lathe and push a button and it replicated.....16 times. The tops have since been ceramic coated.
#142
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Supercharged
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Its been a while and i honselty cant recall the price but it was actaully pretty cheap. I may have posted the price in a thread somewhere? Cool thing is...those dimensions are stored on a disc. Zero out the lathe and push a button and it replicated.....16 times. The tops have since been ceramic coated.
So Tony... how many engines are you planning on building?
#143
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#145
Captain Obvious
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K.I.S.S. => Keep it simple STOOOPID!
That's what I want to do. I think at this point I probably should take a look at the rings and crank bearings. The car does have 136k miles, so there's got to be some wear, best to find out now rather than in 18 months and do it all again.
As for dishing the pistons... we'll see what the mad scientist says, but assuming we just use the thicker HG to make up for loss from decking - that's probably how I'll approach it. Stroker crank... no!
As for methanol injection, not really interested. As long as my compression doesn't go too high, I should be able to run my 8.Xpsi safely.
And BTW, I only had leakage into one cylinder. See post #2 where I'm holding the passenger head. You can see Cyl #7 has brown exhaust valves. All the others are grey. My AFR has always been pretty good, but if this is an indication of some other issue, I'm all ears.
That's what I want to do. I think at this point I probably should take a look at the rings and crank bearings. The car does have 136k miles, so there's got to be some wear, best to find out now rather than in 18 months and do it all again.
As for dishing the pistons... we'll see what the mad scientist says, but assuming we just use the thicker HG to make up for loss from decking - that's probably how I'll approach it. Stroker crank... no!
As for methanol injection, not really interested. As long as my compression doesn't go too high, I should be able to run my 8.Xpsi safely.
And BTW, I only had leakage into one cylinder. See post #2 where I'm holding the passenger head. You can see Cyl #7 has brown exhaust valves. All the others are grey. My AFR has always been pretty good, but if this is an indication of some other issue, I'm all ears.
#146
I wasn't talking about a little nozzel pea-shooting methanol into the intake, which does work, - I was talking about running ethanol as the main fuel.
#147
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Supercharged
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Here's a question that you really should ask yourself: Are you capable to do all this and everything else that has been suggested here, with enough confidence that at the end, your work will be flawless? Or flawless enough to have a good reliable long lasting engine? Just playing devil's advocate here, nothing more.
But it's always good to have someone give you a dose of reality now and then.
#149
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#150
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Well today I decided I had better chick the rings on #7 (the one I had the issue) and crank end play. Rings are good, crank end play is perfect!
#7 piston 360*
That's 0.007" which is about 0.18mm
#7 piston 360*
That's 0.007" which is about 0.18mm